1. Field of the Invention
The present invention relates to a light device and, more particularly, to a light device with high cooing efficiency and low operation noise.
2. Description of the Related Art
Referring to FIGS. 1-3, a conventional light device with a cooling unit is disclosed, wherein the conventional light device labeled as “9” includes a housing 91, a heat sink 92, a cooling fan 93, a light emitting unit 94 and a light-permeable bulb 95. The housing 91 has an assembly opening 911. The heat sink 92 is mounted in the housing 91 via the assembly opening 911 and has a receiving room 921 on one side, a first air channel 922 communicating the outside and the inside of the housing 91, and a second air channel 923 communicating the bottom of the receiving room 921 and the outside of the housing 91. The cooling fan 93 includes a casing 931 forming a cylindrical channel and received in the receiving room 921, a driving motor (not illustrated) having a stator firmly arranged in the cylindrical channel of the casing 931, and a fan wheel 932 mounted on a rotor of the motor to rotate relatively to the casing 931. The light emitting unit 94 is mounted on another side of the heat sink 92 to emit light outside the housing 91 via the assembly opening 911. The light-permeable bulb 95 is mounted on the heat sink 92 and covers the light emitting unit 94.
When the light device 9 having the above structures is in operation, with the motor of the cooling fan 93 and the light emitting unit 94 being electrified, the heat generated by the light emitting unit 94 can be transmitted to the heat sink 92 for the cooling fan 93 to dissipate the heat. Specifically, the fan wheel 932 of the cooling fan 93 can drive the air outside the housing 91 to flow into the housing 91 through the first air channel 922, to pass through the cylindrical channel of the casing 931 from the top of the casing 931 to the bottom thereof, and to be exhausted out of the housing 91 via the second air channel 923. Accordingly, the working temperature of the light emitting unit 94 is kept in a lower range to prolong the life of the light device 9.
However, since the cooling fan 93 of the light device 9 includes the casing 931, the bottom of the casing 931 extending between the receiving room 921 and the second air channel 923 can easily lead to turbulence causing large operation noise, low cooling efficiency and a low flow rate. Besides, the structure of the heat sink 92 is complex for forming the first and second air channel 922, 923, and thus the heat sink 92 of the light device 9 will lead to high manufacture cost.
Therefore, it is necessary to improve this conventional light device 9 to have great smoothness in air guiding, low operation noise, high cooling efficiency and low manufacture cost.